Surface-enhanced Raman spectroscopy (SERS) technology can provide information on a molecular level that is not readily available to other technologies. SERS can also have advantages such as short test time, low water disturbance, direct in situ analysis, high sensitivity and wide test range. In some situations, SERS does not require complicated pre-treatment or a high-purity carrier gas.
Nanoparticles of Ag, Au, and other metals of the first subgroup (including some transition metals) in a SERS active substrate material can effectively strengthen the metal surface plasma resonance, thus enhancing electric field coupling or charge transfer of adsorbed molecules on the substrate surface. This can enhance the Raman response signal of the test object.